Line of departure: immersion and connection

British Army Veteran, London Firefighter & Founder of Line of Departure, Matt Underwood shares his story and how he created a community for connection

As a child, I always loved swimming at Frensham and, of course, paddling in my shorts and wellies. That little boy went on to join the British Army while both the Iraq and Afghanistan conflicts were in full swing. I served for seven years in the Royal Engineers, experiencing a difficult tour of Afghanistan in 2013. This left me questioning “was it all worth it” and feeling that I had damaged that little boy beyond recognition. I could barely look at the pictures of him playing on the beach.

After leaving the services, I was fortunate to find work at St George’s Hospital in Tooting, London. I worked on their helipad for two years, alongside multiple air ambulances, taking in patients from some of the most traumatic medical incidents. I then joined the London Fire Brigade, where I have been for over nine years, serving at one of the busiest fire stations in the country, right in the heart of London. I was surprised by the high levels of trauma exposure our first responders experience daily. These incidents often mirrored experiences I had during my military service.

When I moved my family out of London and back to Surrey, I felt the urge to reclaim my love for wild swimming and found myself regularly taking dips at Frensham Great Pond. I quickly discovered an amazing, supportive community within the cold water swimming world, especially Caroline and Katy from a group called Flow at Frensham.

As a result of my service, I often suffered from nightmares, mostly linked to Afghanistan. But since dipping at Frensham, I noticed an almost immediate improvement in my sleep. After my own positive experience with cold water immersion, I felt compelled to create something that could benefit others. I wanted to help make cold water immersion more accessible for serving military personnel, veterans, and those in the emergency services. This is how Line of Departure was born.

Line of Departure is a cold water immersion group for serving military personnel, veterans, and emergency service workers. It provides like-minded individuals with a space to come together, share time, and experience the perceived benefits of cold water immersion in a supportive, community-based environment. The group runs six to eight sessions each month, scheduled midweek and at weekends to accommodate shift work. It provides a great outing for those stuck in military camps over the weekend or an opportunity to reconnect with old friends from their service.

Each session lasts around an hour. Attendees talk, acclimatize, and then immerse themselves in the water for one to 15 minutes, depending on the temperature. Afterwards, many stay for coffee because the conversations that follow are often just as important as the immersion itself. There is no formal counselling or therapy offered; the model is rooted in peer support and shared experience, encouraging open conversation and positive mental wellbeing through activity rather than clinical intervention.

The attendee list reflects the breadth of the UK’s uniformed services. Participants come from the London Fire Brigade, Surrey FRS, Hampshire & Isle of Wight FRS, Gloucestershire FRS, Surrey Police, Greater Manchester Police, South Central Ambulance Service, St George’s Hospital Helipad Crews, London’s Air Ambulance, and the RNLI. Numerous military units are also represented, including the Royal Engineers, Grenadier Guards, Royal Logistics Corps, Royal Artillery, Royal Green Jackets, Queen’s Gurkha Engineers, Royal Signals, and Royal Navy Clearance Divers.

For veterans, it is a great way to reconnect with the serving military. Serving personnel have found a network in the emergency services that aids their transition, while emergency service personnel have found validation in the growing recognition of the psychological toll their service demands.

Our regular sessions at Frensham Great Pond are free and welcoming to those beginning their cold water journey. We are currently expanding into a second location in London to make our support network more accessible. This summer, we are visiting Divers Cove (Surrey), Bude Sea Pool (Cornwall), and Ullswater in the Lake District. Our ambassador is Krishna Thapa Magar, a former SAS Sergeant Major and globally recognised mountaineer.

In military terms, crossing a “line of departure” signifies the start of an operation – the point at which preparation turns into action. Here, that phrase has been reclaimed. The line is not into conflict, but into community; not towards danger, but towards wellbeing. For me, it reconnected me with the little boy who once wore shorts and wellies, a boy I thought I had lost to the challenges of operational service.

Line of Departure’s online presence continues to expand via Instagram. Search for @lineofdeparturefrenshamponds to find them and access booking. Follow them to show your support and help connect others who need it most.